1. Technical Field
This disclosure relates generally to map rendering, and, more specifically, to functionality of devices providing map applications.
2. Description of the Related Art
Personal navigation devices (e.g., handheld GPS devices and some mobile phones) and other computing devices may implement a mapping application capable of displaying a three-dimensional (3D) map in perspective, indicating depth in the scene. For example, some 3D maps include representations of roads, buildings, bridges, or other structures, and/or geological features, such as hills, bodies of water, etc. By drawing a 3D map in perspective, a mapping application can generate and display a map view that provides visual clues about the relative positions and/or depths of these features in 3D space. Some 3D map applications represent 3D features within maps using simplified shapes (e.g., block shapes), while others represent 3D features using more realistically-shaped models of the 3D features.
Some mapping applications provide techniques for highlighting a selected feature (e.g., a building or another point of interest) or a portion of the scene (e.g., an area within a selected boundary). Some mapping applications highlight a selected feature or portion of a map by changing the color of the selected feature or portion of the map to indicate its selection. Other mapping applications highlight a selected feature or portion of a map by outlining a boundary of the selected feature or portion of the map (e.g., superimposing a wide and/or high-contrast tracing of the boundary over the map). Still other mapping applications highlight a selection by performing a two-dimensional (2D) blur of the image data (i.e., the screen data) in non-selected portions of the map.